If you have an ebook reader or software — Kindle, Nook, Kobo, or iOS device (iPad, iPhone) — the “And Philosophy” series has made a free ebook available that superhero comic readers might be interested in.
Superheroes: The Best of Philosophy and Pop Culture contains selected chapters from various books in that series. Heroes covered include the hot movie stars Captain America and Thor, as well as the Avengers, Iron Man, Spider-Man, and X-Men, plus DC characters Batman, Green Lantern, Superman, and the Watchmen. The 256 pages are being made available to promote the upcoming books Avengers and Philosophy, Spider-Man and Philosophy, and Superman and Philosophy.
Bear in mind that these are academic pieces, not necessarily light reading. And I don’t know why they didn’t make a PDF available for those who don’t have dedicated readers or want to install the software — although Amazon’s Kindle app is available for most computers.